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Relationship of pionium lifetime with pion scattering lengths in generalized chiral perturbation theory

H. Sazdjian
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Abstract

The pionium lifetime is calculated in the framework of the quasipotential-constraint theory approach, including the sizable electromagnetic corrections. The framework of generalized chiral perturbation theory allows then an analysis of the lifetime value as a function of the pion S-wave scattering lengths with isospins I=0,2, the latter being dependent on the quark condensate value.

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H. Sazdjian. 2000-12-18. Relationship of pionium lifetime with pion scattering lengths in generalized chiral perturbation theory. https://arxiv.org/abs/hep-ph/0012228

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